Embodiments of the present invention generally relate to power systems and more specifically to a power system and a method for reducing a high frequency circulating harmonic current flowing between a plurality of converters of the power system.
Power systems, such as solar based power system, wind based power system and the like include a plurality of converters connected in parallel to each other, for example. The power system typically includes a plurality of inductors and a plurality of capacitors coupled to each of the plurality of converters. High frequency circulating harmonic current flows between the plurality of converters due to a low value of impedance of a resonant path formed by the plurality of capacitors and the plurality of inductors. As a result, stress on power semiconductor devices employed in the plurality of converters and cables is increased.
Currently, different techniques have been employed to limit the circulating current between the multiple converters. Typically, a current limiting reactor having a high inductance value is connected to each of the converters for limiting the circulating current. Use of the current limiting reactors corresponding to each converter increases the cost and footprint of the power system. In recent times, a high speed communication network is used to communicatively couple the multiple converters to each other to limit the circulating current. The use of the high speed communication network compromises a reliability of the power system.
Accordingly, there is a need for an enhanced power system and a method for reducing high frequency circulating harmonic current between converters of the power system.